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A341275
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a(n) = 2^(n*(n-1)/2)*Product_{j=0..n-1} (4*j+2)!/(n+2*j+1)!.
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1
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1, 4, 60, 3328, 678912, 508035072, 1392439459840, 13965623033856000, 512247880383410995200, 68683284942451522425323520, 33654191472236763924706696888320, 60248257274480672292932706180054122496, 393994689318303735728047162574735199856230400
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OFFSET
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1,2
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LINKS
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FORMULA
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a(n) ~ exp(1/48) * Pi^(1/4) * 2^(9*n^2/2 + n/2 + 1/3) / (sqrt(Gamma(1/4)) * A^(1/4) * n^(7/48) * 3^(9*n^2/4 + 3*n/4 - 1/24)), where A is the Glaisher-Kinkelin constant A074962. - Vaclav Kotesovec, Feb 08 2021
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MATHEMATICA
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Table[2^(n*(n-1)/2) * Product[(4*j + 2)!/(n + 2*j + 1)!, {j, 0, n-1}], {n, 1, 15}] (* Vaclav Kotesovec, Feb 08 2021 *)
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PROG
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(PARI) a(n) = 2^(n*(n-1)/2)*prod(j=0, n-1, (4*j+2)!/(n+2*j+1)!);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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